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Subject: [RFC][PATCH 00/12] mm: tweak page cache migration
To:     linux-kernel@vger.kernel.org
Cc:     Dave Hansen <dave.hansen@linux.intel.com>, npiggin@gmail.com,
        akpm@linux-foundation.org, willy@infradead.org,
        yang.shi@linux.alibaba.com, linux-mm@kvack.org
From:   Dave Hansen <dave.hansen@linux.intel.com>
Date:   Tue, 06 Oct 2020 13:51:03 -0700
Message-Id: <20201006205103.268F74A9@viggo.jf.intel.com>
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List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

First of all, I think this little slice of code is a bit
under-documented.  Perhaps this will help clarify things.

I'm pretty confident the page_count() check in the first
patch is right, which is why I removed it outright.  The
xas_load() check is a bit murkier, so I just left a
warning in for it.

Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org